基于稳定同位素的5种蔬菜产地真实性判别

Determination of the Geographic Origin Authenticity of Five Vegetables Based on IRMS

为保护蔬菜产地真实性,以上海市场5种常见蔬菜(生菜、茼蒿、辣椒、番茄和黄瓜)为研究对象,应用单因素方差分析上海和其他产地蔬菜的δ^(13)C、δ^(15)N、δ^(2)H和δ^(18)O值差异,并通过主成分分析(PCA)和偏最小二乘判别分析(PLS-DA)建立上海地产蔬菜真实性判别模型。结果表明,上海地产5种蔬菜总的δ^(15)N、δ^(2)H和δ^(18)O值与其他产地蔬菜差异显著(P<0.05),包括番茄的δ^(15)N和δ^(18)O值、辣椒的δ^(2)H值、茼蒿的δ^(15)N值,说明上海本地产蔬菜所施用肥料类型和灌溉水来源与其他产地不同;PCA很难将上海地产蔬菜与其他产地蔬菜识别,PLS-DA最优模型可以很好地判别上海地产生菜(准确率100.00%)、茼蒿(准确率91.67%)和番茄(准确率85.71%)的真实性,辣椒和黄瓜的产地真实性判别模型仍需进一步优化,PLS-DA模型的重要变量为δ^(15)N、δ^(2)H和δ^(18)O值,进一步说明了蔬菜所施用肥料类型和灌溉水来源的差异是实现上海地产蔬菜真实性判别的重要因素。研究结果为蔬菜产地真实性判别提供参考方法。

To protect the geographic origin authenticity of vegetable,five common vegetables(lettuce,garland chrysanthemum,pepper,tomato and cucumber)in Shanghai market were taken as the research objects.The differences ofδ^(13)C、δ^(15)N、δ^(2)H andδ^(18)O values between Shanghai local vegetables and other geographic origin vegetables were analyzed by one-way ANOVA,and principal component analysis(PCA)and partial least squares discriminant analysis(PLS-DA)were used to establish the authenticity discriminant models for Shanghai local vegetables.The results showed that theδ^(15)N,δ^(2)H andδ^(18)O values of Shanghai local vegetables were significantly different from those of other vegetables(P<0.05),including theδ^(15)N andδ^(18)O values of tomato,theδ^(2)H values of pepper and theδ^(15)N values of garland chrysanthemum,suggesting that fertilizer types and irrigation water sources applied to Shanghai vegetables were different from those of other regions vegetables.PCA was difficult to identify Shanghai vegetables from other origins vegetables.The optimal PLS-DA models could well distinguish the authenticity of Shanghai lettuce(accuracy rate of 100.00%),garland chrysanthemum(accuracy rate of 91.67%)and tomato(accuracy rate of 85.71%).The authenticity discriminant models of pepper and cucumber still need to be further optimized.The importance variables of PLS-DA model areδ^(15)N,δ^(2)H andδ^(18)O values,further indicating that the differences of fertilizer types and irrigation water sources are important factors to realize the authenticity discrimination of Shanghai local vegetables.The results can provide a reference method for the authenticity identification of vegetable.